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Mac disk images: any real difference between 'master' and 'compressed'?

Mac disk images: any real difference between 'master' and 'compressed'?

When creating a disk image (.cdr or .dmg) from a physical CD or DVD on Mac (using Disk Utility > New Image) one can choose between 'CD\DVD Master‘ and 'compressed'.

Asked by: Guest | Views: 160
Total answers/comments: 2
Guest [Entry]

Master is uncompressed and does not need to be expanded to be restored. A compressed image is obviously smaller, but must be uncompressed before it can be manipulated. If performance is a concern in restoring the image then use a Master. If you can live with a little longer time, but a smaller footprint, go with compressed. Both will end up with the same result.
Guest [Entry]

"The .dmg format is Mac OS X–only. A compressed .dmg disk image will have a checksum so that you can verify that the file is not damaged.

If you make a master (.cdr/.iso) image, it can also be burned using other operating systems. And, depending on the filesystem of the CD/DVD, you might even be able to mount the master image."